This invention relates to the field of satellite and spacecraft design, and in particular to a design architecture that provides a cross-mission set of modules and design rules that minimize the delay time between the definition of requirements and the launch of a spacecraft that satisfies these requirements.
There is an increasing need for rapid requirements-to-launch turn-around time for deploying spacecraft. In military applications, for example, dynamic changes in political or military situations often result in a need for surveillance and/or communications satellites in orbits having particular coverage areas, with different situations requiring different satellite capabilities. In research applications, universities or other agencies often require spacecraft platforms that are easy-to-configure to support particular research objectives. In each of these applications, and others, there is a need to launch a payload without incurring the substantial time and costs associated with the development of a spacecraft to support the payload.
U.S. Pat. No. 6,283,416, “SPACECRAFT KERNEL”, issued 4 Sep. 2002 to Richard D. Fleeter and Scott A. McDermott, and incorporated by reference herein, teaches the advantages of designing and providing a spacecraft interface with kernel components on one side of the interface, and components that depend on either the spacecraft configuration or the mission-specific system on the other side of the interface. The kernel components are both functionally and physically independent of the vehicle configuration and function, and physically independent of the mission-specific system. The kernel components typically include communications equipment for communicating with an earth station, a power management system for receiving variable power input and providing regulated power output, and a processing system that receives commands from the earth station and provides corresponding commands to other subsystems, on both sides of the interface, in a standard format. By providing communications, power management, and command processing in a kernel that is independent of the spacecraft configuration and the spacecraft's mission, the same kernel can be used on multiple spacecraft, thereby reducing the time and cost associated with the design and testing of new spacecraft, as well as potentially reducing manufacturing cost.
Although the spacecraft kernel design architecture provides a means to provide potentially re-usable designs, it does not necessarily provide for rapid development of a spacecraft. As noted above, the kernel components are independent of the space vehicle's configuration. However, the packaging of one set of kernel components for a given space vehicle's configuration may be unsuitable for use in another space vehicle. Correspondingly, a re-packaging of the kernel components for a given configuration typically requires substantial mechanical design and testing time, and may not be able to take advantage of prior tests or certifications conducted with the original configuration of the kernel components.
In like manner, by limiting the re-usable kernel components to those items that are independent of the spacecraft configuration, the number of potentially re-usable designs is substantially reduced. Most spacecraft, for example, use solar panels to provide the energy required to operate the spacecraft and mission-specific components. However, because the spacecraft configuration typically dictates how and where such panels can be placed relative to the other components, most solar panel arrangements are custom-designed for each spacecraft.
U.S. Pat. No. 6,260,804, “FUNCTIONALLY AND STRUCTURALY MODULAR PARALLELOGRAM-SHAPED SPACECRAFT”, issued 17 Jul. 2001 to Anderson et al., and incorporated by reference herein, discloses a modular spacecraft design wherein each functional module of the spacecraft can be independently manufactured. Each module has a similar cross-section, so that the modules can be assembled into a spacecraft by stacking them along the vertical axis. Flats are provided at the vertices of the parallelogram-shaped modules for connection to vertical channel members that serve to join the modules together. This referenced patent does not address the design of each module, and of particular note, does not address the functional interface among the modules, other than to note that the channel members facilitate the routing of electrical cables. That is, the modular mechanical design of this referenced patent provides a structure that facilitates the independent manufacture of functional components, and potentially the rapid assembly of these components, but does not address techniques for reducing the time to design a spacecraft based on a given set of functional requirements.
It is an object of this invention to provide a spacecraft architecture that facilitates rapid requirements-to-launch turnaround time. It is a further object of this invention to provide a spacecraft architecture that facilitates the use of previously designed and tested modules in a variety of configurations. It is a further object of this invention to provide a standard for spacecraft design that optimizes the potential for the use of designed modules in other spacecraft.
These objects, and others, are achieved by a spacecraft architecture and accompanying standard that allows for the creation of a spacecraft using an assortment of modules that comply with the standard. The standard preferably includes both mechanical and electrical compatibility criteria. To assure physical/mechanical compatibility, the structure of each module is constrained to be compatible with any other compatible module. To minimize the interference among modules, the extent of each module in select dimensions is also constrained. To assure functional compatibility, a common communication format is used to interface each module, and each public-function module is configured to respond to requests for function capabilities that it can provide to other modules. Each module is preferably designed to provide structural support to the assemblage of modules, and an anchor module is provided or defined for supporting the entire assemblage and coupling the assemblage to other structures, such as a launch vehicle.
Throughout the drawings, the same reference numerals indicate similar or corresponding features or functions. The drawings are included for illustrative purposes and are not intended to limit the scope of the invention.